Supercharger Noisy
*** UPDATED BY TSB 91-11B-11 DATED 06/14/91POSSIBLE CAUSE ACTION
Rough engine idle ^ Perform engine idle diagnosis.
Refer to COMPUTERIZED ENGINE CONTROLS,
ELECTRONIC FUEL INJECTION, or IGNITION SYSTEMS for
appropriate diagnostic procedures.
Air/vacuum leaks/high pitch whistle ^ Perform INDUCTION SYSTEM LEAK TEST.
Exhaust leak ^ Check for loose, damaged or
burnt rubber tube to PFE sensor or
EGR valve.
Bypass valve actuator not opening ^ Check that the actuator valve
is operating.
^ Check that the bypass vacuum tube
is connected.
^ Check for kinked or damaged vacuum
tube.
^ Check for stuck or restricted valve.
^ Check for stuck bypass actuator rod.
^ Check stop adjustment of actuator.
Low supercharger oil level ^ Check supercharger oil level. Replace
supercharger if there is no oil.
Foreign object ingestion ^ Remove supercharger outlet adapter.
Visually inspect rotors for damage from
foreign object ingestion. If rotors are
damaged, replace supercharger.
Gear rattle ^ A rattle/growl at engine idle and
just off idle. This is a typical noise
that does not effect durability or
function.
Note: Rough engine idle and bypass valve
actuator not opening can cause excessive
gear rattle.
Chirp ^ A high pitch noise (similar to belt
chirp) at engine idle and just off idle.
This is typical noise that does not affect
durability or function.
Note: Rough engine idle and bypass valve
actuator not opening can cause excessive
gear chirp.